Why Cooked Greens Are Safe
A variety of delicious greens are mega-sources of important nutrients.
Spinach, chard, kale, beet greens, arugula and broccoli rabe (shown here) are mega-sources of important nutrients, including beta carotene, a potent antioxidant, and vitamin K, which helps to maintain strong bones. It’d be a shame if the September 2006 spinach crisis (when E. coli bacteria tainted spinach from several counties in California, causing at least one death) scared you away from leafy greens.
There’s no reason to nix greens. Eliminating greens from your diet means losing out on easy, one-hit ways of meeting nutrient needs. For example, just half a cup of cooked kale provides four times your recommended daily dose for vitamin K.
So how do you ensure that the greens you buy are 100 percent safe? Fact is, you can’t. Obviously, all fresh greens should be cleaned, but washing them won’t remove all potentially present bacteria. “Research has shown that bacteria can migrate to the interior of leafy greens, through cut edges or damaged leaves,” says Sue Snider, Ph.D., professor of food safety at the University of Delaware. “Once it’s in the tissue, it’s difficult to remove.”
Cooking greens at 160°F, for at least 15 seconds, will kill all E. coli. (The temperatures at which you sauté easily exceed this—be sure all leaves get enough direct contact with the pan—and remember, water boils at 212°F.) But what about that crisp spinach or arugula salad?
“Unless you like cooked lettuce, you need to live by the fact that [an E. coli outbreak] is an anomaly,” says Douglas Archer, Ph.D., professor of food science at the University of Florida. “Think about how many [about 9 million] spinach servings Americans consume on any given day, without anything going wrong.”
Bottom line: “Nothing in life is totally risk-free,” says Robert B. Gravani, Ph.D., professor of food science at Cornell University, “but fresh produce, in general, is safe—and researchers, policy makers and farmers are working to make it even safer.” Also, don’t forget: eating lots of produce helps prevent chronic conditions, including heart disease, diabetes and cancer.